1. Field of the Invention
The present invention relates to a multidirectional laser indicator, and in particular, to a multidirectional laser indicator having a simplified adjustment method for adjusting a laser module.
2. Description of the Prior Art
There are many kinds of multidirectional laser indicators available in the current market. One example is illustrated in Republic of China (Taiwan) Patent No. 329,303, entitled “Laser Leveler of Automatic Horizontal Calibration Capability and Convenient Displacement Adjustment”, which has laser units arranged at the front and the four sides (upper, lower, left, and right side) of the projecting platform of the laser leveler for forming a crossing projection using a horizontal and a vertical projecting line, a left and a right vertical projecting line, and upper and lower projecting points.
Another example is illustrated in Republic of China (Taiwan) Patent No. 391,913, entitled “Ink Line Maker”, which has a vertical projector and a horizontal projector, with which a normal degree may be measured. If four sets of vertical laser modules are installed in the apparatus and are arranged symmetrically, then the four sets of vertical laser modules may project four vertical lines. This is shown in FIG. 1 of the present application, where the laser indicator 10 projects four vertical laser beams L1-L4 and one horizontal laser beam L5. An ideal situation is for the four vertical laser beams L1-L4 to join with each other at the top of the laser indicator 10, with the vertical laser beam L1 intersecting perpendicularly with the horizontal laser beam L5. Unfortunately, since the laser module is prone to experience displacement after extended use, not only will the horizontal laser beam L5 be skewed (i.e., no longer horizontal), but the four vertical laser beams L1-L4 may also be unable to be joined at one point. As a result, the laser module will need to be re-calibrated.
FIGS. 2A and 2B illustrate a conventional calibration method. The laser module 20 is generally arranged inside a shell 22 having adjusting bolts 21a, 21b installed on the upper side and the lower side of the shell 22, respectively. One of two sets of adjusting bolts 21c+21d and 21e+21f is installed on each side of the shell 22, with all the adjusting bolts 21a-21f threaded through the shell 22 and contacting the laser module 20. As a result, the laser module 20 can be rotated and displaced by rotating the adjusting bolts 21a-21f so that the position of the laser module 20 can be calibrated. However, the major shortcoming of this six-point adjusting method is that it is very time-consuming and difficult to properly implement. The adjustment can be very tedious, especially for an indicator that has four laser modules. Furthermore, by providing six adjusting bolts in a laser module 20, the material cost is increased as well.